Tagged: Fish Die Off

05 Jul

Comments Off on Nature’s Way of Leveling the Playing Field

Nature’s Way of Leveling the Playing Field


From the Reader’s Write section of the Stouffville Free Press

These periodic die-offs may be nature’s way of leveling the playing field.

In the last couple of weeks Musselman’s Lake has experienced a fish die-off similar, but less severe in numbers, to what occurred in the spring of 2009.

There are a number of similarities between this fish die-off and that of 2009. As in 2009 the dying fish are almost exclusively black crappie, as well, both incidences occurred in the early spring when the Crappie are breeding.

Sunfish nesting in Musselman's Lake.

Sunfish nesting in Musselman’s Lake. Photo Dr. Brian Laing

Sunfish, a close relative, are seen mating and nesting as I write this. A water quality issue would affect more than one species of fish.

All of this leads us to believe that the crappie die-off that we have just experienced is caused by the same thing that caused it in 2009, namely, the unusually warm weather followed by a drop in temperature timed just when the crappie are breeding. This theory is further supported by the fact that almost all of the fish are of breeding size, the young fry are not affected.

If the Crappie were not spawning they would have stayed in the deeper cooler water and not been subjected to the water temperature fluctuations. As it is, the breeding fish stay in the shallow water and are stressed becoming prone to a bacterial infection by Columnaris flexibacter.

Columnaris is always present in fish, but typically becomes an issue only in stressed fish.

Postmortems in 2009 confirmed this as the cause at that time. Due to the similarities of the two die-offs, we have not performed postmortems this year, but are confident that the cause of the two incidents is the same.

There is potential ‘silver lining’ to this crappie die-off. Crappie are an aggressive species recently introduced to the lake (likely through release of baitfish). I have seen their young surround a sunfish nest and slowly eat all the eggs. As the male sunfish chases off one juvenile crappie another moves in and eats some eggs. The sunfish returns to the nest and chases off the new interloper while a third rushes in to eat some more eggs. In very little time the sunfish nest is empty.

Because of survival instincts like this, the crappie population has dramatically increased since they were introduced to the lake and is putting pressure on other species.

These periodic die-offs may be nature’s way of leveling the playing field.

Dr Brian Laing


Town and Country Animal Hospital




Related Links

Natural Occurrence and No Cause For Alarm

Update of the Crappie Die-Off

Phil Bannon Mounts A Cleanup

Crappie Update

It’s Crappie!


07 Jun

Comments Off on Natural Occurrence and No Cause For Alarm

Natural Occurrence and No Cause For Alarm


Nature At Work…no cause for alarm

Nature at WorkRecently residents are again seeing a fish die off.  This is something that we have seen before and again are looking into with the same vigour as before.  The last die off was in 2009 and that information, including the results of fish autopsies can be found in the Related Links section below if anyone is interested.  We would encourage all waterfront residents to please scoop as many dead fish as possible out of the water and dispose of them either through burying or the green bin.

This year we have seen very little algae so far but a much greater bounty of weeds coming to the surface. We have found that on years where the ice comes off early and the weeds can get established that we do not get an early algae bloom, in years like last year where there is a late melt followed by weeks of warm weather the algae can get a good hold.  This is all natural and exactly what the experts tell us to expect.  This has nothing to do with lake pollution and everything to do with the natural life cycle of a living body of water.

Lake Report Final_cvr1

CLICK ON IMAGE for the Water Quality and Management of Musselman’s Lake Report

In 2014 we were very fortunate to have Geranium homes contract Hutchinson Environmental Sciences conduct the most extensive study of Musselman’s Lake ever.  Please click on the report image to view this very extensive and enlightening report.

We will keep everyone posted with results of the investigation into this years die off.

Dr. Brian Laing, has been looking into this years fish die off, which consist 99% crappie and mostly breeding size.
They were breeding last week before the sunfish started mating season started. The recent unusual warm weather while they are breeding stresses them and makes them susceptible to bacterial infections.
This is a completely natural occurrence and no cause for alarm.

Related Links

Crappie Story
Update of the Crappie Die-Off
Crappie Update
It’s Crappie!